Mix water and falafel mix together in a bowl; let stand for 10 minutes. Form mixture into 12 patties, about 1/2-inch thick.
Fry falafel patties in hot oil until golden brown and crisp. Transfer cooked falafel to a paper towel-lined plate; season with salt. Cool falafel to room temperature; break into pieces.
Whisk sour cream, milk, cucumber, parsley, and 1/8 teaspoon salt together in a bowl until dressing is smooth and creamy; refrigerate.
Spread greens onto serving plates. Arrange tomatoes, avocado, bacon, eggs, feta cheese, and falafel in rows over the greens. Drizzle dressing over each salad.